Hard, impact resistant, polyurethane products are particularly desirable. However, in attempting to obtain such products the art has met with some difficulty, particularly with regard to the selection of a suitable curing agent. Many diamines have been considered for use as a curing agent for isocyanate terminated polyurethane prepolymers, but most are generally dificient in some respect.
U.S. Pat. No. 3,188,302 discloses a class of diamine curing agents which are particularly suitable for use in preparing such polyurethane products. However, these materials also present difficulties, including toxicity problems during processing which includes the curing step.
U.S. Pat. No. 3,681,290 also discloses a class of diamine curing agents. These materials are also dificient, for example, in pot life.
The present invention is directed to novel diamine cured polyurethane products and to novel diamine curing agents suitable for use with isocyanate terminated prepolymers.